Signal-component extraction apparatus and signal-component extraction method

Abstract

In signal-component extraction, an input signal is delayed to generate a delayed input signal. The input signal is adaptively filtered with filter coefficients, to generate a filtered signal. The filtered signal is subtracted from the delayed input signal to generate an error signal. A preset reference value is divided by an amplitude of the input signal to generate a gain value. The filter coefficients are derived based on a value obtained by multiplying the input signal and error signal by the gain value or a square of the gain value.

1 . A signal-component extraction apparatus comprising:
 a delayer configured to delay an input signal to generate a delayed input signal;   an adaptive filter configured to adaptively filter the input signal with filter coefficients, to generate a filtered signal;   a subtractor configured to subtract the filtered signal from the delayed input signal to generate an error signal;   a coefficient controller configured to divide a preset reference value by an amplitude of the input signal to generate a gain value; and   a coefficient deriver configured to derive the filter coefficients based on a value obtained by multiplying the input signal and error signal by the gain value.   
     
     
         2 . The signal-component extraction apparatus according to  claim 1 , wherein the coefficient deriver derives the filter coefficients based on a value obtained by multiplying the input signal and error signal by a square of the gain value. 
     
     
         3 . A signal-component extraction method comprising the steps of:
 delaying an input signal to generate a delayed input signal;   adaptively filtering the input signal with filter coefficients, to generate a filtered signal;   subtracting the filtered signal from the delayed input signal to generate an error signal;   dividing a preset reference value by an amplitude of the input signal to generate a gain value; and   deriving the filter coefficients based on a value obtained by multiplying the input signal and error signal by the gain value.   
     
     
         4 . The signal-component extraction method according to  claim 3 , wherein the filter coefficients are derived based on a value obtained by multiplying the input signal and error signal by a square of the gain value.